Effect of different metal ions on the oxidative damage and antioxidant capacity of hyaluronic acid.

Degradation and the antioxidative effect of Na-, Zn-, Co-, Cu-, and Mn-hyaluronic acid (HA) associates were studied. Our findings revealed the protective effect of certain counterions against ROS-induced HA degradation. We could also separate the antioxidative effect of certain counterions from that of the HA by examining the effect of the counterions in their free ionic forms.